Authorizing the Use of a Motor Vehicle

ABSTRACT

A method for authorizing the use of a motor vehicle, having a first and second antenna spatially remote from one another, includes emitting, from the first vehicle antenna, a first signal that is received by an identification transmitter antenna of a portable identification transmitter. The method includes establishing at least one spatial component of a first electromagnetic field of the received first signal using an angle-resolving magnetic field sensor, emitting, by the second vehicle antenna, a second signal that is received by the portable identification transmitter antenna, and establishing at least one spatial component of the second electromagnetic field of the received second signal using the angle-resolving magnetic field sensor. An angle between the established at least one spatial component of the first electromagnetic field and the established at least one spatial component of the second electromagnetic field is determined, and a first authorization signal for authorizing the use of the motor vehicle to the motor vehicle is transmitted by the portable identification transmitter when the established angle exceeds a predetermined threshold value.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of PCT International Application No.PCT/EP2016/075339, filed Oct. 21, 2016, which claims priority under 35U.S.C. § 119 from German Patent Application No. 10 2016 204 750.7, filedMar. 22, 2016, the entire disclosures of which are herein expresslyincorporated by reference.

This application contains subject matter related to U.S. applicationSer. Nos. ______ (Atty Docket No. 080437.PB528US), entitled “Authorizingthe Use of a Motor Vehicle” and Ser. No. ______ (Atty Docket No.080437.PB530US), also entitled “Authorizing the Use of a Motor Vehicle,”both of which are filed on even date herewith.

BACKGROUND AND SUMMARY OF THE INVENTION

The invention relates in particular to a method for authorizing the useof a motor vehicle which has at least one first and one second antenna,wherein the first antenna and the second antenna are spatially remotefrom one another. The motor vehicle is in particular a two-wheeled orfour-wheeled motor vehicle.

In such known methods, it is desirable to further improve same againstmanipulations.

An object of the invention is in particular to provide a method forauthorizing the use of a motor vehicle having improved protectionagainst manipulations.

This object is achieved in particular by a method for authorizing theuse of a motor vehicle having the features of the independent methodclaim. Advantageous refinements of the method according to the inventionare the subject of the dependent method claims.

The method according to the invention is based on a method forauthorizing the use of a motor vehicle, in particular a two-wheeled orfour-wheeled motor vehicle, which has at least one first and one secondantenna, wherein the first antenna and the second antenna are spatiallyremote from one another, by way of a portable identification transmitterthat has an identification transmitter antenna.

Other objects, advantages and novel features of the present inventionwill become apparent from the following detailed description of one ormore preferred embodiments when considered in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows embodiment of a method in accordance with the principles ofthe invention.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring to FIG. 1, in a first step 10, the first vehicle antenna emitsa first signal that is received by the identification transmitterantenna.

In a second step 20, the identification transmitter establishes at leastone of the spatial components of the first electromagnetic field of thereceived first signal, preferably using an angle-resolving magneticfield sensor.

In a third step 30, the second vehicle antenna emits a second signalthat is received by the identification transmitter antenna.

In a fourth step 40, the identification transmitter establishes at leastone of the spatial components of the second electromagnetic field of thereceived second signal, preferably using the angle-resolving magneticfield sensor.

In a fifth step 50, a first computer, preferably a computer in theidentification transmitter, establishes the angle at least between theestablished spatial component of the first electromagnetic field of thereceived first signal and the established spatial component of thesecond electromagnetic field of the received second signal, and in asixth step 60, the identification transmitter transmits an authorizationsignal for authorizing the use of the motor vehicle to the motor vehicleonly when the established angle exceeds a predetermined threshold value.

In summary, the method according to the invention, with the aid of atleast two spatially separate or remote transmitters, may be used todetermine the position of the receiver or of the identificationtransmitter in an angle-resolved manner. If the signals of the remotetransmitters are forwarded by a repeater for manipulative purposes, thepropagation time is increased and the angle information is lost. Theangle-resolving method according to the invention recognizes suchmanipulation of the transmission path by recognizing the parallelism ofthe signals from the identification transmitter and said identificationtransmitter prevents the emission of an authorization signal.

In one particularly preferred refinement of the method according to theinvention, it is provided that the identification transmitter isprovided with a motion sensor. The motion sensor preferably establisheswhether it or whether the identification transmitter is being moved, andthe identification transmitter transmits the first and/or a secondauthorization signal for authorizing the use of the motor vehicle to themotor vehicle only when the motion sensor establishes a movement of theidentification transmitter.

According to one preferred development of the method according to theinvention, it is provided that the motion sensor repeatedly establisheswhether it is being moved. When a movement is recognized or established,the motion sensor in each case preferably provides the occurrence of themovement and/or the type of the movement with a timestamp.

By way of the above optional measures according to the invention,manipulations are additionally made more difficult or avoided.

In one preferred embodiment of the method according to the invention, itis provided that in each case the occurrence of the movement providedwith a timestamp and/or the respective type of the movement providedwith a timestamp are stored in a data store in the identificationtransmitter and/or in a data store in the motor vehicle and retained fora subsequent movement pattern comparison with a reference movementpattern.

As an alternative or in addition, in one embodiment of the methodaccording to the invention, it is provided that the movement patterncomparison is performed by a computer in the identification transmitterand/or by a computer in the motor vehicle, and the identificationtransmitter and/or the motor vehicle provides an authorization signalfor authorizing the use of the motor vehicle only when the computer inthe identification transmitter and/or the computer in the motor vehicleestablishes a predetermined match level between the movement pattern ofthe identification transmitter and the reference movement pattern.

In one particularly preferred refinement of the method according to theinvention, it is provided that the identification transmitter emitsdata, such as an authorization signal, only when it is currently beingmoved.

Furthermore, in one particularly preferred embodiment of the methodaccording to the invention, it is provided that the reference movementpattern is the movement pattern of a typical approach to the vehicle.

In one refinement of the method according to the invention, thereference movement pattern is collected for each authorized party and/orfor each identification transmitter and stored in the identificationtransmitter and/or in the associated motor vehicle for a subsequentmovement pattern comparison.

According to one preferred embodiment of the method according to theinvention, it is provided that the motion sensor is formed by anacceleration sensor.

The above optional measures according to the invention are suitable formaking manipulations even more difficult or for avoiding them.

As an alternative or in addition, in one refinement of the methodaccording to the invention, it may be provided that the time differencebetween the emission of the first signal by the first vehicle antennaand the emission of the second signal by the second vehicle antenna isselected to be so short in time—but other than zero—that theidentification transmitter carried by the driver is substantially notmoved as the driver approaches the vehicle. As a result, theestablishment of the angle at least between the established spatialcomponent of the first electromagnetic field of the received firstsignal and the established spatial component of the secondelectromagnetic field of the received second signal is substantially notfalsified or not unusable as a result of the movement of the driver oras a result of the movement, connected therewith, of the identificationtransmitter.

In one development of the method according to the invention, it isprovided that the motor vehicle has a further third antenna that isspatially remote from the first and the second antenna, respectively,and that, in the same way, the angle at least between the establishedspatial component of the first electromagnetic field of the receivedfirst signal and the established spatial component of the thirdelectromagnetic field of a third signal emitted by the third antenna andreceived by the identification transmitter is determined.

These optional measures too are advantageously suitable for furtherreducing the risk of manipulations or making them considerably moredifficult.

According to one embodiment of the method according to the invention, itis provided that the spatial components, established by theidentification transmitter, of the first electromagnetic field of thereceived first signal are the x, y and z components of theelectromagnetic field of a first Cartesian coordinate system.

In one refinement of the method according to the invention, it isprovided that the spatial components, established by the identificationtransmitter, of the second electromagnetic field of the received secondsignal, the x, y and z components of the electromagnetic field aresubstantially the components with reference to the first Cartesiancoordinate system, substantially because the Cartesian coordinate systemor reference system underlying the establishment of the componentschanges spatially only slightly upon slight movements of theidentification transmitter in very short time periods between therepeated establishment of the angles.

According to one development of the method according to the invention,it is provided that the spatial components, established by theidentification transmitter, of the third electromagnetic field of thereceived third signal, the x, y and z components of the electromagneticfield are substantially those of the first Cartesian coordinate system.

In one preferred embodiment of the method according to the invention, itis provided that at least one first vector from the x, y and zcomponents, established by the identification transmitter, of the firstelectromagnetic field of the received first signal and one second vectorfrom the x, y and z components, established by the identificationtransmitter, of the second electromagnetic field of the received secondsignal is formed computationally, and their scalar product is formedcomputationally from these two vectors.

In one likewise preferred development of the method according to theinvention, it is provided that the angle between the two vectors isdetermined computationally with the aid of the scalar product.

The above optional measures are advantageously suitable for implementingthe method according to the invention in a cost-effective manner.

In one preferred embodiment of the method according to the invention, itis provided that the established angle exceeds a predetermined thresholdvalue of substantially zero degrees, in particular a threshold valuegreater than 1 to 10 degrees, preferably 1 to 5 degrees.

According to one preferred development of the method according to theinvention, it is provided that the threshold value, which is greaterthan zero degrees, is increased as the distance of the identificationtransmitter from the vehicle decreases, wherein the distance ispreferably determined via a propagation time measurement between thesignals that are exchanged between vehicle and identificationtransmitter.

In one preferred embodiment of the method according to the invention, itis provided that the first, second and third antenna each transmit on anidentical or different frequency in the frequency range of 20 kHz to 140kHz, preferably on about 125 kHz, preferably in a temporally offsetmanner.

By way of these above optional measures, the method according to theinvention may be configured to be even more secure.

The invention advantageously makes it possible to provide a vehicleaccess system for authorizing the use of a motor vehicle, in which thevehicle access system brings about the execution of at least one step ofa method according to the invention.

The invention further makes it possible to provide a vehicle accesssystem according to the invention for authorizing the use of a motorvehicle, in which the vehicle access system executes or brings about theexecution of at least one step of a method as claimed in one of thepreceding claims and the identification transmitter is a radio key or asmartphone, preferably having an identification transmitter softwareapplication, such as what is known as an app.

The invention further proposes a vehicle access system according to theinvention for authorizing the use of a motor vehicle, in which theidentification transmitter is a smartphone provided with a computerchip, a radio vehicle key provided with a computer chip or a chip cardhaving a computer chip.

The invention further proposes a vehicle access system according to theinvention for authorizing the use of a motor vehicle, in which theidentification transmitter has a sensor for determining or establishingan electromagnetic field and/or the components of the electromagneticfield that has been produced by one or more vehicle antennae in theregion of the identification transmitter.

The invention proposes an immobilizer for authorizing the use of a motorvehicle, which immobilizer brings about the execution of at least onestep of a method according to the invention.

The invention likewise proposes a motor vehicle that brings about theexecution of at least one step of a method according to the invention oris involved in the execution.

Lastly, a computer program product for controlling at least oneprocessor that brings about the performance of at least one step of amethod according to the invention is proposed.

The foregoing disclosure has been set forth merely to illustrate theinvention and is not intended to be limiting. Since modifications of thedisclosed embodiments incorporating the spirit and substance of theinvention may occur to persons skilled in the art, the invention shouldbe construed to include everything within the scope of the appendedclaims and equivalents thereof.

What is claimed is:
 1. A method for authorizing the use of a motorvehicle having at least one first and one second antenna, wherein thefirst antenna and the second antenna are spatially remote from oneanother, the method comprising the acts of: emitting, from the firstvehicle antenna, a first signal that is received by an identificationtransmitter antenna of a portable identification transmitter;establishing, by the portable identification transmitter, at least onespatial component of a first electromagnetic field of the received firstsignal using an angle-resolving magnetic field sensor; emitting, by thesecond vehicle antenna, a second signal that is received by the portableidentification transmitter antenna; establishing, by the portableidentification transmitter, at least one spatial component of the secondelectromagnetic field of the received second signal using theangle-resolving magnetic field sensor; establishing, by a computer inthe vehicle, an angle at least between the established at least onespatial component of the first electromagnetic field and the establishedat least one spatial component of the second electromagnetic field; andtransmitting, by the portable identification transmitter, a firstauthorization signal for authorizing the use of the motor vehicle to themotor vehicle only when the established angle exceeds a predeterminedthreshold value.
 2. The method as claimed in claim 1, wherein theportable identification transmitter comprises a motion sensor thatestablishes whether the motion sensor or the portable identificationtransmitter is being moved, and wherein the portable identificationtransmitter transmits the first and/or a second authorization signal forauthorizing the use of the motor vehicle to the motor vehicle only whenthe motion sensor establishes a movement of the portable identificationtransmitter.
 3. The method as claimed in claim 2, wherein the motionsensor repeatedly establishes whether the motion sensor is being movedand, when a movement is recognized or established, the motion sensor ineach case provides an occurrence of the movement and/or type of themovement with a timestamp.
 4. The method as claimed in claim 3, whereinin each case the occurrence of the movement and/or type of movementprovided with a timestamp are stored in a data store and retained for asubsequent movement pattern comparison with a reference movementpattern.
 5. The method as claimed in claim 4, wherein the subsequentmovement pattern comparison with the reference movement pattern isperformed by a computer in one of the portable identificationtransmitter and in the motor vehicle, and wherein one or both of theportable identification transmitter and the motor vehicle provide anauthorization signal for authorizing the use of the motor vehicle onlywhen a predetermined match level is established between the subsequentmovement pattern and the reference movement pattern.
 6. The method asclaimed in claim 1, wherein the portable identification transmitteremits the authorization signal only when in motion.
 7. The method asclaimed in claim 4, wherein the reference movement pattern is a movementpattern of a typical approach to the motor vehicle.
 8. The method asclaimed in claim 4, wherein the reference movement pattern is collectedfor each authorized user and/or for each portable identificationtransmitter and stored in the portable identification transmitter and/orin the motor vehicle.
 9. The method as claimed in claim 1, wherein atime difference between emitting the first signal by the first vehicleantenna and emitting the second signal by the second vehicle antenna isselected to be short in time such that the portable identificationtransmitter carried by a driver of the motor vehicle is substantiallynot moved as the driver approaches the vehicle, and therefore saidestablishing the angle is substantially not unusable due to movement ofthe driver or due to movement of the portable identificationtransmitter.
 10. The method as claimed in claim 1, wherein the motorvehicle has a third antenna that is spatially remote from the first andthe second antenna, respectively, and wherein the method furthercomprises determining an angle at least between the established spatialcomponent of the first electromagnetic field and an established spatialcomponent of the third electromagnetic field of a third signal emittedby the third antenna and received by the portable identificationtransmitter.
 11. The method as claimed in claim 1, wherein the at leastone spatial component of the first electromagnetic field of the receivedfirst signal include x-, y- and z-components of an electromagnetic fieldof a first Cartesian coordinate system.
 12. The method as claimed inclaim 11, wherein the at least one spatial component of the secondelectromagnetic field of the received second signal are the x-, y- andz-components of an electromagnetic field substantially the componentswith respect to the first Cartesian coordinate system.
 13. The method asclaimed in claim 10, wherein the at least one spatial component of thethird electromagnetic field of the received third signal are the x-, y-and z-components of an electromagnetic field substantially those of thefirst Cartesian coordinate system.
 14. The method as claimed in claim 1,further comprising: computing a first vector from the x-, y- andz-components of the first electromagnetic field of the received firstsignal; computing a second vector of the x-, y- and z-components of thesecond electromagnetic field of the received second signal; andcomputing a scalar product from the first vector and the second vector.15. The method as claimed in claim 14, further comprising computing anangle between the two vectors based on the scalar product.
 16. Themethod as claimed in claim 1, wherein the threshold value increased as adistance of the portable identification transmitter from the motorvehicle decreases, and wherein the distance is determined via apropagation time measurement between signals exchanged between vehicleand portable identification transmitter.
 17. The method as claimed inclaim 1, wherein the first, second and third antennas transmit with atime offset in a frequency range of 20 kHz to 140 kHz.
 18. A vehicleaccess system configured to authorize use of a motor vehicle, whereinthe system comprises at least one first vehicle antenna and one secondvehicle antenna, wherein the first vehicle antenna and the secondvehicle antenna are located at a spatial distance from one another, andwherein the system is configured to: emit, from the first vehicleantenna, a first signal that is received by an identificationtransmitter antenna of a portable identification transmitter; establish,by the portable identification transmitter, at least one spatialcomponent of a first electromagnetic field of the received first signalusing an angle-resolving magnetic field sensor; emit, by the secondvehicle antenna, a second signal that is received by the portableidentification transmitter antenna; establish, by the portableidentification transmitter, at least one spatial component of the secondelectromagnetic field of the received second signal using theangle-resolving magnetic field sensor; establish, by a computer in thevehicle, an angle at least between the established at least one spatialcomponent of the first electromagnetic field and the established atleast one spatial component of the second electromagnetic field; andtransmit, by the portable identification transmitter, a firstauthorization signal for authorizing the use of the motor vehicle to themotor vehicle only when the established angle exceeds a predeterminedthreshold value.
 19. The vehicle access system as claim in claim 18,wherein the portable identification provider is one of a radio key, asmart phone or a chip card having a computer chip.